14 Aug 2023 | 06:47 AM UTC
US: High temperatures forecast to persist across southern and southeastern regions through at least Aug. 16 /update 4
Heatwave forecast across parts of the southern and southeastern US through at least Aug. 16. Transport and power disruptions possible.
Event
Forecast models indicate excessive temperatures are likely to persist across parts of the southern and southeastern US through at least Aug. 16. High temperatures are likely from Florida north to the Carolinas and west to Texas and Oklahoma, with the most excessive heat over Texas and into the Lower Mississippi Valley. Forecast models indicate daily high temperatures of the mid-90s in Florida and the Carolinas, the upper 90s in portions of the Southeast, the low 100s in Oklahoma and the Lower Mississippi Valley, and the mid 100s in portions of Texas. The temperatures combined with high humidity are likely to result in heat indices as high as 43-49 C (110-120 F) across many parts of the affected area. The heat is forecast to moderate slightly in the northern portion of the region from Aug. 16. The high daytime temperatures and limited overnight cooling pose a significant health risk, especially for those without effective cooling and adequate hydration.
As of late Aug. 13, the US National Weather Service (NWS) has issued excessive heat warnings across parts of eastern Texas, southeastern Arkansas, Louisana, Mississippi, Alabama, most of Georgia, and western and northern Florida. Heat advisories are in effect across much of the rest of the affected area. Officials could update and extend the coverage of weather alerts over the coming days.
The high temperatures may result in increased energy and water demand and an increased risk of heat-related illnesses such as heat exhaustion and heat stroke. Authorities advise the general public to avoid prolonged exposure to direct sunlight, wear loose and light clothing, and stay hydrated.
Hazardous Conditions
The extended period of oppressive heat and dry conditions may produce ideal circumstances for wildfire growth throughout the region. Heatwaves also pose a threat to vulnerable groups - such as the elderly, children, pregnant women, and those with respiratory illnesses - due to the increased possibility of heat stroke or heat exhaustion during prolonged exposure to high temperatures. These health risks could also extend to relatively healthy individuals during significant heatwave events.
Transport and Utilities
Very high temperatures may warp rail tracks and force passenger and freight trains to operate at reduced speeds. Road surface damage is also possible, and overheated vehicles may worsen traffic problems in urban areas where congestion is already a problem. Commercial trucking disruptions might occur as very high temperatures put more stress on vehicles, making tire blowouts more common. Major flight disruptions are unlikely, but general aviation disruptions are possible, and some airfreight carriers could reduce cargo loads. High temperatures could lead to an increased demand for electricity, which might trigger localized brownouts or blackouts, exacerbating hazardous conditions when air conditioning is no longer possible.
Advice
Monitor local media for weather updates and related advisories. During heat waves, remain indoors in air conditioning when possible. If outdoor activities are necessary, frequently rest in shaded areas; avoid activity during the hottest times of the day. Stay well hydrated by drinking plenty of fluids. Avoid alcoholic beverages, which are dehydrating - drink bottled water or water that has been boiled. Wear loose-fitting, light-colored clothing. Cotton fabrics are more cooling than synthetics. Promptly seek medical attention if signs of heat exhaustion or heat stroke develop. Charge battery-powered devices in case prolonged electricity outages occur.
